Sheet piler with stagger piling mechanism



Feb. 20, 1968 BUCCICONE SHEET FILER WITH STAGGER FILING MECHANISM 4 Sheets-Sheet 1 Filed Oct. 14, 1966 IN VENTOR DAR/O BUCC/CONE 3L2 QMQ A TT'YS.

D. BUCCICONE 3,369,806

SHEET FILER WITH STAGGER FILING MECHANISM Feb. 20, 1968 4 Sheets-Sheet Filed Oct. 14, 1966 INVENTOR DAR/0 BUCC/CONE Feb. 20, 1968 D. BUCCICONE SHEET FILER WITH STAGGER FILING MECHANISM INVENTOR 4 Sheets-Sheet 5 Filed Oct. 14, 1966 DAR/0 BU CC/CONE fiMWfiM ATT' Y5.

Feb. 20, 1968 D. BUCCICONE SHEET FILER WITH STAGGER FILING MECHANISM 4 Sheets-Sheet Filed Oct. 14, 1966 I. i .J M, l 1 wl: A F T LIF CFC:

t C s c E N m0 mm VC m0 u B m R A 0 ATT' United States Patent 3,369,806 SHEET PILER WITH STAGGER FILING MECHANISM Dario Buccicone, Gary, Ind., assignor to Bucciconi Engineering Co., Inc., Gary, Ind., a corporation of Indiana Filed Oct. 14, 1966, Ser. No. 586,795 17 Claims. (Cl. 271-68) This invention relates to apparatus for piling metal sheets and is more particularly concerned with improvements in a piler machine which has incorporated therein mechanism for arranging the sheets in staggered relation in the pile.

In a normal piling operation, metal sheets are advanced to a piling area by an overhead magnetic conveyor which releases the sheets at the proper time for deposit on the pile in the piling area beneath the conveyor. End stop and back stop mechanisms are provided at opposite ends of the piling area for-engagement by the leading and trailing edges of the sheets so as to guide the same while they settle by gravity onto the pile with their edges brought into vertical alignment. In some operations, it is desirable to pile the sheets in a group of a predetermined number, arranged in staggered relation, so as to facilitate removal of the sheets from the machine, enabling the operator to grasp a group of the sheets for removal at one time from the pile, Mechanisms have heretofore been provided which are adapted to arrange the sheets initially in tiered relation with each group or tier of the sheets being staggered at an edge thereof relative to the adjacent tiers of sheets. One such mechanism is disclosed in Buccicone Patent No. 3,020,810, dated Feb. 13, 1962 wherein stagger piling is accomplished by the use of an end stop mechanism which mounted in suspended relation on a movable carriage supported on the machine for adjustment along the longitudinal center thereof. This mechanism operates satisfactorily in piling operations in which all of the sheets are deposited on the pile but it is not suitable for use on piler machines in which it is necessary that sheets may be permitted to pass from one piler to another. In some operations it is desirable to employ a number of piling machines arranged in alignment so as to enable sheets to be piled in a number of different piles with some of the sheets passing through one or more of the piler machines. This requires an end stop mechanism which will not interfere with the sheets which are to be passed through the machine. A Piler Mechanism for Metal Sheets is disclosed in Buccicone Patent No. 3,256,011, dated June 14, 1966, which employs an end stop mechanism supported on a movably mounted carriage forming cross frame having wheels riding in track formations so as to enable the mechanism to be adjusted longitudinally of the machine. The end stop mechanism is suspended beneath magnetic rail units which constitute an overhead conveyor and provision is made for moving the end stop mechanism out of the path of a sheet when it is desired to pass a sheet through the machine. A general object of the present invention is to provide an improved sheet piling machine having an end stop mechanism incorporated therein which in its normal position enables sheets to be passed through the machine, when desired, and which also enables those sheets which are piled by the machine to be arranged in staggered relation on the pile.

It is a more specific object of the invention to provide in a sheet piler machine having an overhead sheet carrying conveyor and associated stop mechanisms for arresting the movement of the sheets and guiding the same as they are released by the conveyor and dropped by gravity onto the pile wherein the end stop mechanism is located at all times below the pass line so as to enable selected sheets to be passed through the machine without requiring 3,369,806 Patented F eb. 20, 1968 the end stop mechanism to be moved out of the plane in which such sheets travel.

It is another object of the invention to provide an improved sheet piling machine having incorporated therein an overhead conveyor which receives the sheets from a processing line and advances them either through the machine or into position for deposit by gravity on a support beneath the same and end stop and back stop members positioned below the pass line which are engaged by the leading and trailing edges, respectively, of the sheets released from the conveyor for piling and which are so constructed that they may be operated, when desired, to guide the sheets into final position on the pile between the members with the sheets arranged in staggered relation.

It is a further object of the invention to provide a mechanism for handling metal sheets wherein the sheets are carried by an overhead magnetic conveyor and selected sheets are released to drop by gravity onto the top of a pile beneath the conveyor, the mechanism having sheet stopping devices which are adapted to guide into predetermined position the leading and trailing edges, respectively, of the sheets which are to be deposited on the pile, with the end stop mechanism including bumper devices having sheet stopping elements which are movable so that in one position thereof the sheets will be piled in staggered relation and in another position normal piling will result with the sheet stopping elements being disposed in both positions below the pass line of the sheets so as to maintain clearance above the same for sheets which are to be passed through the machine.

It is another object of the invention to provide in an apparatus of the type described end stop and back stop members wherein the end stop members are mounted below the bottom face of the conveyor so as to provide a clear path for sheets which are passed through the machine and movable bumper stop plates are provided with mechanism for moving the same into and out of vertically disposed stagger piling position along a path which remains below the pass line of the sheets so as to avoid any interference with sheets which are passed through the machine.

It is a still further object of the invention to provide in a piler mechanism of the type described end stop members including main bumper pads and auxiliary bumper pads which are adjustable between a lowered top of the pile engaging position and an upper out-of-use position and which auxiliary bumper pads have an associated finger member normally held in extended position forwardly of the sheet engaging face of the main bumper pads so as to engage beneath the edges of the sheets while they are being piled, which finger member is automatically withdrawn from beneath the edges of the sheets upon upward movement of the auxiliary bumper pads without disturbing the position of the sheets on the pile.

These and other objects and advantages of the invention will be apparent from a consideration of the piler machine which is shown by way of illustration in the accompanying drawings wherein:

FIGURE 1 is a side elevation of a sheet piler having incorporated therein mechanism embodying the principal features of the invention, the view being partly schematic and with portions broken away or omitted;

FIGURE 2 is a longitudinal vertical section with portions broken away and to an enlarged scale, the view showing the end stop mechanism in side elevation;

FIGURE 3 is an end elevation of the end stop mechanism of FIGURE 2;

FIGURE 4 is a plan view with portions broken away showing the end stop mechanism of FIGURE 2;

FIGURE 5 is a cross section taken on the line 5-5 of FIGURE 4;

FIGURE 6 is a cross section taken on the line 6-6 of FIGURE 2;

FIGURE 7 is a fragmentary section taken on the line 77 of FIGURE 2, to an enlarged scale;

FIGURE 8 is a view taken on the line 88 of FIG- URE 2, to an enlarged scale and with portions broken away;

FIGURE 9 is a longitudinal section taken on the line 99 of FIGURE 8, with portions broken away; and

FIGURE 10 is a fragmentary view showing a portion of FIGURE 2 with the stagger bumper assembly in retracted position.

The apparatus which is illustrated in the drawings and which embodies the principal features of the present invention is an improvement on the apparatus disclosed in Buccicone Patents Nos. 2,918,852, dated Dec. 29, 1959; 3,020,810, dated Feb. 13, 1962; and 3,256,011, dated June 14, 1966. The apparatus is particularly designed for use in combination with rail-type magnetic conveyors of the character disclosed in Buccicone Patents Nos. 2,600,- 475, dated June 17, 1952; 2,642,174, dated June 16, 1953; and 3,229,805, dated Jan. 18, 1966. It is understood, however, that it is not intended to limit the mechanism herein disclosed for use with magnetic rail-type conveyors but it is contemplated that it could be used with other types of overhead conveyors where piling of the sheets in staggered relation is desirable.

In the apparatus, as illustrated in FIGURE 1 of the drawings, the metal sheets S are received from a shear or other equipment in a processing line on the conveyor 10 which delivers or feeds the sheets to the entry end of an overhead magnetic-type conveyor 11. The magnetic conveyor 11 comprises a plurality of transversely spaced, rail-like conveyor units 12 each of which includes a pair of longitudinally spaced sheaves 13 and 14, at least one of which is power driven, and sheet carrying endless belts 15 extending around the sheaves. The conveyor rail units 12 are supported at their opposite ends on cross beams 16 and 17 which are suitably mounted on end support frames 18 and 19, respectively. Each rail unit 12 contains a plurality of magnet assemblies (not shown) which are adapted to hold the sheets S against the underside of the belts 15 so that the belts can advance the sheets toward the right in FIGURE 1.

A suitable control means is provided for the magnet assemblies so as to cause the sheets to be held against the lower runs of the belts 15 while they are advanced toward the right and to permit sheets which it is desired to deposit in a pile beneath the conveyor to be released so as to drop onto the pile. Sheets which are to pass through the conveyor are permitted to continued and pass out of the piler at the exit forming right end thereof. The specific control mechanism will depend upon the type of magnet assembly employed in the conveyor rail units 12.

A lift arrangement or a vertically adjustable table 21 is provided beneath the conveyor 11 which supports the pile 22 o-f-sheets S. An end stop mechanism 23 and a back stop mechanism 24 are arranged on the machine in longitudinally spaced relation beneath the conveyor 11. The back stop mechanism 24 is supported in fixed position on the end frame 18 at one end of the table or lift 21 while the end stop mechanism 23 is mounted for movement longitudinally of the conveyor 11 so that the machine may be adjusted for handling sheets of different lengths. The mechanisms thus far referred to, except for the end stop mechanism 23, are not per se a part of the present invention but can be of any standard or desired construction, and, therefore, are not shown or described in greater detail. The prior patents referred to above disclose suitable magnetic rail-type conveyor units with which the present invention may be employed and these patents may be referred to for details not herein described. The rail units may incorporate either electromagnet assemblies or permanent magnet assemblies with suitable controls for providing the required magnetic force as desired.

The end stop mechanism 23 and the back stop mechanism 24 are spaced in a horizontal direction, when the machine is used for stagger piling, so that the normal distance between their oppositely disposed main faces or bumper pads is greater than the dimension of the sheets in the same direction in order that the sheets may be arranged in the pile staggered relation, the stop mechanisms being so constructed and operated that one end of the sheets in each group or tier is positioned adjacent the face of the main bumper pad of one of the stop mechanisms, while the other end thereof is spaced from the face of the main bumper pad of the other stop mechanism a sufficient distance, generally in the neighborhood of two inches, to enable the handler to position his fingers beneath the edge of the uppermost group or tier of sheets at one end of the pile. The back stop mechanism 24 is positioned and arranged so that the sheets may enter the machine from the conveyor 10 and advance beneath the conveyor 11. Clearance is provided for movement of the sheets without any interference across the top of the back stop 24.

The end stop mechanism 23 (FIGURE 1) is mounted on an overhead supporting carriage 25 which is movable lengthwise of the conveyor 11 and which may be in the form of a transversely extending frame carried in longitudinal track formations and having a suitable adjusting mechanism, for example, as shown in Patent No. 3,256,- 011. The carriage 25 supports a horizontally disposed, transversely extending bottom frame 26 with a bottom plate 27 suspended by side frame mechanism 28 from the carriage 25. The frame 26 is of sufiicient width to accommodate the widest sheet which the machine is designed to handle. The end stop mechanism 23 is mounted on the top face of the cross plate 27. It comprises a bumper stop frame 30 (FIGURES 2 to 6) which is generally L-shaped when viewed in side elevation (FIGURE 2) with the long leg 31 thereof extending in a horizontal plane and supported for horizontal reciprocating movement in spaced relation above the frame plate 27 and with the short leg 32 thereof extending downwardly at the side of the plate 27 which faces in the direction of the entrance end of the conveyor 11. The bumper frame 30 includes laterally spaced, parallel side frame members 33 and 33 which are of generally rectangular cross section and provide top and bottom rail-forming surfaces 35, 36 and 35, 36 which constitute tracks for riding on flanged wheels 37, 38, 39 and 37', 38' 39', the latter being disposed in triangular arrangement and rotatably mounted in parallel, laterally spaced, upstanding support plates 40 and 40. The support plates 40 and 40' have bottom flanges 41 and 41' which are bolted orotherwise secured to the top face of the plate 27.

A cushion forming air cylinder 42 is mounted on a suitable support bracket 42' on the plate 27 between the two vertical plates 40 and 40' with the piston 43 thereof extending horizontally and having an end cap 44 positioned to engage a depending bumper bracket 45 on the bumper frame 30. The bracket 45 is L-shaped when viewed in side elevation with one leg thereof depending below the bottom surfaces 36, 36' of the frame members 33 and 33' and in the path of the piston 43. The other leg of the bracket 45 is bolted or otherwise secured between the side frame members 33 and 33'. A cushion member 46 having a pad forming rubber block 47 is fastened on the opposite face of the depending leg of the bracket 45 in position to engage the upstanding side wall of a housing 48 extending transversely on the plate 27 which, in the form of the apparatus shown, may enclose an adjusting screw 49 for side guide mechanisms (not shown) for the machine.

A pair of wheels 50 and 50' are mounted on pins 51, 51' journaled in bearing forming members of a supportiug bracket 52 which is bolted or otherwise secured on the forward face of the housing 48. The wheels 50 and 50' provide support for the forward portion of the horizontal leg 31 of the frame 30, with the bottom surfaces 36, 36' of the side rails 33 and 33' riding on the rollers and 50.

Main bumper pads and 55' are supported in transverse alignment and in a vertical plane outboard of the side frame members 33 and 33' by means of brackets 56 and 56 secured on the outer side faces of the frame members 33 and 33' at the forward end of frame 30 which have vertically disposed pad support members 57 and 57. The pads 55 and 55' have suitable facing for engagement by the leading edges of the sheets as they are thrown against the vertical face of the assembly.

A movable stagger bumper assembly 60 (FIGURES 2, 3 and 4) is supported by the frame 30 at the forward end thereof which includes a pair of supporting chain members 61 and 61 mounted for movement in T-shaped guide slots 62 and 62' which are provided in the inside faces 63 and 63' of the frame side members 33 and 33' and which extend along both the vertical and horizontal legs of the frame 30. The chains 61 and 61' carry a plurality of roll brackets 64, each having end plates 65 and 65 attached to the chain plates and on the outboard ends of which rollers 66 are supported on pins 67 extending between the pairs of oppositely disposed end plates 65 and 65 so as to travel with the chains 61 and 61', when the latter are moved. The chains 61 and 61' are connected at their uppermost ends by a cross bar 68. The cross bar 68 is provided on its rearward facing edge with a pair of spaced ears 69 between which a cross pin 70 extends. The cross pin 70 is adapted to be received in the downwardly opening slot 72 in the eye forming member 73 on the end of an operating piston rod 74. The piston rod 74 extends from an air cylinder 75 which is supported at the forward end on a cross bar 76 extending between the side bars 33 and 33' and at its rearward end is pivotally connected at 77 to ear forming members 78 extending from a cross bar 80 at the end of the frame 30. The air cylinder 75 is operative to move the stagger bumper assembly 60 from an operative vertical position, as shown in FIG- URE 2, to an inoperative horizontal position as shown in FIGURE 10. A bumper pad 81 of leather, rubber or similar flexible material is mounted as shown in FIGURE 2 with the lower end attached by the bracket 82 to the ends of chains 61 and 61. Back up blocks 83 are attached to the bracket 82 at the lower end of the pad 81 adjacent the ends of each of the chains 61 and 61'. end the pad 81 is curved back over the frame 30 and passes between rollers 84, 85 and 86 on a roller bracket 87 which is secured in upstanding relation on the top face of the cross member 68 at the upper end of the chains 61 and 61'. The bracket 87 has a pair of upstanding parallel side plates 88 and 88 between which rollers 84, 85 and 86 extend, the latter being arranged in triangular relation as shown in FIGURE 2 with the bumper pad 81 passing between the same and the uppermost rollers 85 and 86 serving to support a sheet S for passing above the same end to protect the mechanism if the sheet drops below the normal pass line. The bracket 87 has a guard forming portion 89 extending over the connection of the chains with the piston 74.

A stagger lip assembly 90 (FIGURES 2, 8 and 9) is provided for co-operation with the bumper members. The stagger lip assembly 90 is supported on a bracket 82 at the forward edge of the support plate 27. The lip assembly 90 comprises a supporting arm assembly at 93 and a lip forming plate 94 swingably mounted on the free end thereof, and adapted in the operative position to extend forwardly of the vertical face of the stagger pad 60 as shown in FIGURE 2. The free end of the arm 93 extends between a pair of spaced rollers 95 and 96 at the lower end of the chains 61 and 61' which are journaled in the rear portion of the bracket 82 so that the assembly swings upwardly when the stagger bumper assembly 60 is raised. The lip forming plate 94 is attached to the free end of At its upper 6 the arm assembly 93 by pin 97 extending between a pair of ear forming members 98, 98' at the free end of the lowermost link plate 100 on the arm 93. A top link plate 101 is disposed in parallel link forming relation with the bottom link plate 100 and both of these plate members have side flanges which are disposed in edgefacing relation along each side of the plates so as to form between the plates 100 and 101 a compartment for housing a spring balancing mechanism and portions of a movement control mechanism for the lip member 94. The plates 100 and 101 are connected to the bracket 92 at one end by vertically aligned pivot pins 102 and 102 and at their other ends the plates are connected by parallel link members 103 and 103 which are pivoted on pins 104 and 104' mounted in the ear forming members 98 and 98 on the bottom plate 100 and corresponding ear forming members on the top plate 101. The spring balancing mechanism comprises a pair of coil springs 105 and 105 extending along opposite sides of the plates 100 and 101 and held in position by guard plates 1% and 106 upstanding on the bottom plate 100. The springs 105 and 105 are mounted between the plates 100 and 101 in an identical manner and only one will be described, the corresponding mounting members for the other being indicated by the same numerals primed. The spring 105 has its opposite ends seated on the stern portions of keeper members 107 and 108. The keeper member 107 has an axial bore which is threaded to receive a cap screw 110 t on which the keeper 107 is adjustably mounted. The cap screw 110 is loosely mounted in an aperture in a lug plate 111 upstanding from the plate 100 and held against axial movement by nut assembly 112. At the other end of the spring 105 the keeper 108 is seated against a lug plate 113 which depends from the top plate member 101.The force of spring 105 tends to urge the arm assembly 90 in a clockwise direction about its supporting pivots 102 and 102' so as to balance the weight of the arm and lip assembly 90 and facilitate lifting the same when the stagger assembly 60 is moved to the inoperative position shown in FIGURE 10. The movement control mechanism for the lip member 94 comprises the pull rod 115 which is slidably mounted in suitable apertures in spaced lug plates 116 and 117 upstanding in parallel relation from the plate 100. The pull rod 115 is pivotally connected at 118 to a short length of chain 120 which extends around the pivot pin 97 and is anchored to the lip 94 so that pulling or pushing on the chain 120 through rod 115 will swing the lip 94 about its pivot 97. A coil spring 121 is carried on the pull rod 115 with one end abutting the lug 116 and the other end abutting a clamp-type collar forming member 122 mounted for axial adjustment on the rod 115 and normally abutting the lug 117. The rod 115 carries on its free end a head forming member 123 with a curved end surface 124 for cooperation with a similar curved surface 125 on a lug member 126 depending from the top plate 101. The curved surfaces 124 and 1250f the two members 123 and 126 work against each other as pivotal movement of the arm 93 causes relative movement between the plates 100 and 101 so that when the arm 93 moves upwardly the lip member 94 is held down against the top sheet on the pile. The arrangement resules in the lip member 94 remaining at approximately the same angle relative to its vertical position.

In the operation of the piler, the end stop 23 is adjusted longitudinally of the machine for the length of sheet being handled and when stagger piling is desired, the stagger bumper assemblies are moved to operative position. These may be moved automatically by proper control mechanisms so that the desired number of sheets is staggered with the stagger bumper assemblies being moved alternately into and out of their operative position. The end stop bumper assembly 23 is located at all times below the normal pass line of the sheets so as to provide clearance for movement of sheets which are to be passed the top of the pile regardless of through the piler and not released for deposit on the pile 22. The stagger bumper stop assembly 60 and the lip assembly 90 are moved to the position shown in FIGURE 2 for operation when the stagger assembly of the back stop 24 is moved to the inoperative position and the sheets are piled against the main back stop pad and guided onto the lip 94 by the end stop stagger assembly 60. When the required number of sheets has been deposited in the tier the stagger assembly in the back stop 24 is moved into operative position and the stagger assembly 60 in the end stop 23 is moved to the inoperative position shown in FIGURE 10. The cylinder 75 operates to retract the stagger bumper assembly by pull on the chains 61 and 61 which carry the stagger bumper pad 81 and the associated mechanism. The retraction of the chains 61 and 61' moves the pad 81 and the associated elements into a horizontal plane at the top of the frame 30 as shown in FIGURE 10 with the top surface of the pad 81 being located below the pass line for the sheets and with the rollers 85 and 86 on the frame 87 providing a support above the top surface of the pad 81 for receiving any sheet which may be dropped by the conveyor.

While particular materials and specific details of construction have been referred to in describing the form of the apparatus which is illustrated, it will be understood that other materials and equivalent structural details may be resorted to within the spirit of the invention.

I claim:

1. A sheet piler comprising an overhead conveyor and an end stop mechanism disposed below the conveyor and having a main bumper pad positioned in a generally vertical plane for engagement with the leading edges of successive sheets as they are released by the conveyor for deposit in a pile in front of the stop mechanism, said end stop mechanism including a main bumper frame on which said main bumper pad is mounted, a frame-like supporting carriage mounted for adjustment longitudinally of said conveyor, a supporting platform suspended from said carriage and having a horizontal track forming means thereon for receiving said bumper frame, means for cushioning the horizontal movement of said bumper frame on impact of the leading edges of successive sheets with said main bumper pad, a stagger bumper device adapted to provide in one position thereof a sheet engaging surface in a generally vertical plane in front of said main bumper pad, the bumper frame for said main bumper pad having a track formation with vertical and horizontal portions, an articulated stagger bumper carriage for said stagger bumper device mounted for movement on said track formation, and means for moving said stagger bumper carriage between said one position and another position where said stagger bumper pad is disposed horizontally below the .path of the sheets advanced across the top of said end stop mechanism by said overhead conveyor.

2. A sheet piler comprising an overhead conveyor and an end stop mechanism extending below the conveyor with the vertical face positioned for engagement with the leading edges of successive sheets as they are released by the conveyor for deposit in a pile in front of the stop mechanism, a support carriage for said end stop mechanism mounted for adjustment along said conveyor, 21 frame suspended from said support carriage and having a platform spaced below the sheet carrying bottom face of the conveyor, a bumper plate frame mounted on said platform for reciprocating movement in a horizontal path, a vertically disposed bumper pad mounted on said bumper plate frame, means for cushioning the horizontal movement of said bumper plate frame upon said bumper pad being struck by the leading edges of successive sheets released by said overhead conveyor, and a stagger bumper mechanism movably mounted on said bumper plate frame which includes a stagger bumper pad adapted to be positioned in vertical sheet engaging relation in front of said main bumper pad or in a horizontal out-of-the-way position on the top of said bumper plate frame where said stagger bumper pad is spaced below the path of sheets carried on the bottom face of the conveyor, said bumper plate frame having track formations with vertical and horizontal sections, means mounting said stagger bumper mechanism for movement in said track formations and an operating cylinder on said bumper plate frame having a piston connected to said stagger bumper mechanism for moving said stagger bumper mechanism along said vertical and horizontal portions of said track formations.

3. In a sheet handling machine having an overhead conveyor arranged to advance sheets selectively to a piling area and beyond said piling area, an end stop mechanism disposed beneath the conveyor and having a main bumper pad positioned in a generally vertical plane for engagement with the leading edges of sheets which are released by the conveyor for deposit in a pile in front of the end stop mechanism, said end stop mechanism including a main bumper frame on which said main bumper pad is mounted, a supporting carriage mounted for adjustment longitudinally of said conveyor, a frame suspended from said carriage and having means thereon for supporting said main bumper frame for horizontal movement, means for cushioning the horizontal movement of said main bumper frame resulting from impact of the leading edges of successive sheets with said end stop mechanism, a stagger bumper device movably mounted on said main bumper frame and having a stagger bumper pad adapted to provide in one position thereof a sheet edge engaging surface in a generally vertical plane in front of said main bumper pad, said main bumper frame having a track formation with vertical and horizontal portions, means forming an articulated carriage for said stagger bumper device mounted for movement on said track formation, and means for moving said articulated carriage between said one position and another position where the sheet engaging surface of said stagger bumper pad is disposed horizontally below the path of the sheets advanced across the top of said end stop mechanism by said overhead conveyor.

4. In a machine for handling sheets which comprises an overhead sheet carrying conveyor supported at a piling station and adapted to release selected sheets for gravity deposit on a pile beneath the conveyor or to advance the sheets beyond the piling station, an end stop mechanism mounted below the conveyor so as to arrest the forward movement of and guide onto a pile sheets which are released by the conveyor in front of the end stop mechanism, said end stop mechanism comprising a supporting frame, a main bumper plate frame mounted on said supporting frame for horizontal movement, a bumper pad on said main bumper plate frame providing a substantially vertical face which is adapted to be engaged by the leading edges of sheets released for piling by said overhead conveyor, means for cushioning horizontal movement of said main bumper plate frame which results from engagement of said sheets with the end stop mechanism, and a stagger bumper device movably mounted on said main bumper plate frame which device include a flexible stagger bumper pad and a carriage forming support therefor which is adapted to be positioned so that said stagger bumper pad provides a vertically extending, sheet engaging surface in front of said main bumper pad and means to move said carriage forming support in a vertical and horizontal direction to a position at the top of said main bumper frame where the sheet engaging surface of the stagger bumper pad is disposed horizontally a sufficient distance below the bottom face of said conveyor to permit sheets to be advanced by said conveyor beyond the piling station without interference.

5. In a machine for handling sheets as recited in claim 4, and the carriage forming support for said stagger bumper pad comprising a pair of laterally spaced chains and connecting members in the form of roller frames extending between said chains, and rollers on said roller frames on which said flexible stagger bumper pad rides.

6. In a machine for handling sheets as recited in claim 4, and the carriage forming support for said stagger bumper pad comprising a pair of laterally spaced chains, connecting cross members at the ends of said chains, said stagger bumper pad being connected at its end to the cross member at the free end of the carriage forming support and extending toward the opposite end thereof and said means to move said carriage forming support comprising a power cylinder having its piston connected to the cross member at said opposite end thereof.

7. In a machine for handling sheets as recited in claim 5, and said carriage forming support having a bracket upstanding at the upper side of said main bumper plate frame and horizontally disposed, vertically spaced rollers mounted thereon between which the end portion of the stagger bumper pad is guided so as to extend horizontally.

8. In a machine for handling sheets as recited in claim 4, and said stagger bumper device including a lip forming member mounted on a pivotal arm which lip member is positioned at the bottom end of the stagger bumper pad so as to rest on the top margin of the pile when the stagger bumper pad is in sheet engaging position, and said arm having a slidable connection with the carriage forming support for the bumper pad so as to travel with the carriage forming support when the latter is moved.

9. In a machine for handling sheets as recited in claim 8, and the slidable connection for said arm with said carriage forming support comprising a pair of spaced rollers on said carriage forming support between which said arm is slidably confined.

10. In a machine for handling sheets as recited in claim 8, and said arm having spring means to balance the weight thereof when raised by movement of said carriage forming support.

11. In a machine for handling sheets as recited in claim 8, and said lip member being pivoted to the free end of said arm and spring biasing means for holding said lip member in predetermined position relative to the top of the pile.

12. In a machine for handling sheets as recited in claim 4, and said carriage forming support being articulated so as to travel in a curved path between a vertical and a horizontal position on said main bumper frame.

13. In a machine for handling sheets as recited in claim 4 wherein said main bumper plate frame comprises laterally spaced side frame members having confronting track formations with vertical and horizontal sections and the carriage forming support for said stagger bumper pad includes chain members riding in said track formations.

14. In a machine for handling sheets as recited in claim 8, and said arm comprising a pair of plates disposed in parallel spaced planes so as to form a housing there between, said plates each being pivoted at a fixed point whereby they form a parallel linkage, and Weight halancing springs in the housing formed by the plates which are operative upon pivotal movement of the arm.

15. In a machine for handling sheets as recited in claim 8, and said arm comprising a pair of plates disposed in parallel spaced planes so as to form a housing therebetween, said plates being pivoted at corresponding ends so as to form a parallel linkage, said lip member being pivoted to the free end of one of said plates and having a connection with a spring biased pull rod housed between said plates which is operated by relative movement of said plates to hold the lip member in predetermined relation to the top of the pile as the arm is raised and lowered.

16. In a machine for handling sheets as recited in claim 4, and said main bumper plate frame having a vertically disposed bumper pad supporting section and a horizontally disposed carriage forming section, and vertically spaced, horizontally disposed rollers on said supporting frame forming a guideway for receiving said carria-ge forming section.

17. In a machine for handling sheets as recited in claim 16, and said means for cushioning horizontal movement of said main bumper plate frame comprising an air cylinder mounted on said supporting frame and having its piston engaging with co-operating means on said main bumper plate frame so as to resist retractive movement of said main bumper plate frame.

References Cited UNITED STATES PATENTS RICHARD E. AEGERTER, Primary Examiner. 

1. A SHEET PILER COMPRISING AN OVERHEAD CONVEYOR AND AN END STOP MECHANISM DISPOSED BELOW THE CONVEYOR AND HAVING A MAIN BUMPER PAD POSITIONED IN A GENERALLY VERTICAL PLANE FOR ENGAGEMENT WITH THE LEADING EDGES OF SUCCESSIVE SHEETS AS THEY ARE RELEASING BY THE CONVEYOR FOR DEPOSIT IN A PILE IN FORM OF THE STOP MECHANISM, AND END STOP MECHANISM INCLUDING A MAIN BUMPER FRAM ON WHICH SAID MAIN BUMPER PAD IS MOUNTED, A FRAME-LIKE SUPPORTING CARRIAGE MOUNTED FOR ADJUSTMENT LONGITUSINALLY OF SAID CONVEYER, A SUPPORTEING PLATFORM SUSPENDED FROM SAID CARRIAGE AND HAVING A HORIZONTAL TRACK FORMING MEANS THEREON FOR RECEIVING SAID BUMPER FRAME, MEANS FOR CUSHIONING THE HORIZONTAL MOVEMENT OF SAID BUMPER FROM ON IMPACT OF THE LEADING EDGES OF SUCCESSIVE SHEETS WITH SAID MAIN BUMPER PAD, A STAGGER BUMPER DEVICE ADAPTED TO PROVIDE IN ONE POSITION THEREOF A SHEET ENGAGING SURFACE IN A GENERALLY VERTICAL PLANE IN FRON OF SAID MAIN BUMPER PAD, THE BUMPER FRAME FOR SAID MAIN BUMPER PAD HAVING A TRACK FORMATION WITH VERTICLE AND HORIZONTAL PORTIONS, AN ARTICULATED STAGGER BUMPER CARRIAGE FOR SAID STAGGER BUMPER DEVICE MOUNTED FOR MOVEMENT ON SAID TRACK FORMATION, AND MEANS FOR MOVING SAID STAGGER BUMPER CARRIAGE BETWEEN SAID ONE POSITION AND ANOTHER POSITION WHERE SAID STAGGER BUMPER PAD IS DISPOSED HORIZONTALLY BELOW THE PATH OF THE SHEETS ADVANCED ACROSS THE TOP OF SAID END STOP MECHANISM BY SAID OVERHEAD CONVEYOR. 